Elevator control mechanism



Feb. 3, 1942. E. L. DUNN 2,271,998

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E. L. DUNN ELEVATOR CONTROL MECHANISM Filed Sept. 12, 1940 8 Sheets-Sheet 3 ///////Ilmi\\\\\\\\ W L nm INVENTOR BY mull I ATTORNEY Feb. 3, 1942.

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ELEVATOR CONTROL MECHANISM Filed Sept. 12, 1940 8 Sheets-She t, 6

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ELEVATOR CONTROL MECHANISM V Filed Sept. 12, 1940 8 Sheets-Sheet 8 SSI3 mlgn

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61M L {IN INVENTOR BY ATTORNEY Patented Feb. 3, 1942 UNITED STATES PATENT OFFICE ELEVATOR CONTROL MECHANISM Edward Lee Dunn, Livingston, N. J., assignor to Otis Elevator Compan y, New York, N. Y., a

30 Claims.

The invention relates to control mechanism for elevators and especially to such mechanism which is actuated in accordance with movement of the elevator car.

There are many control operations for elevator systems which are dependent upon the positions of the cars in their hatchways. In certain installations, for example, push buttons are procar may be utilized to control the lighting of the hall lanterns at the various floors, dispatching and scheduling of the elevators, door operation and levelling of the car. Although these various control mechanisms may be arranged separately, there is a distinct advantage in grouping them together as a machine driven from the elevator car. Such machines are usually termed selector machines.

In installations in which the slow down and stopping of the car at floors is effected automatically, it is desirable that the speed of the car during retardation be controlled to efiect retardation at a rate which is as fast as possible without its being objectionable to the average passenger and such that the car is brought down to a desired low speed from which an accurate stop may readily be made. A variable voltage system, that is, one in which direct current is supplied to the elevator hoisting motor from variable voltage dynamo electric generating means, is particularly suitable for this purpose as the Voltage of the generator may be very readily and accurately controlled to control the speed of the elevator car. In higher speed installations, the car cannot get up to full speed in making short floor runs and it has proved a difiicult problem to control acceleration and retardation on such runs to bring the car down to a low speed from which an accurate stop may be made, without sacrifice of smoothness of operation. time consumed in making the run, or some other factor of performance.

One of the principal features of the invention is the provision of mechanism for controlling both acceleration and retardation of the car in such way that these operations are accomplished at the desired rate and so as to bring the car to a desired low speed from which an accurate stop may be made regardless of the length of the run. More specifically, this feature involves distance control of both acceleration and retardation of the car. Thus, by fixing the speed of the car at all points in its travel in accordance with the position of the car with respect to the floor from which it started and with respect to the floor at which a stop is to be made, the same rate of acceleration and retardation may be readily obtained for all lengths of run and accurate stops at the floors may be readily effected.

Another feature is the provision of control means effective on short floor runs to cause a decrease in the rate of acceleration to start at a variable distance in advance of the point at which slow down begins, dependent upon the length of the run, to enable acceleration to be reduced to zero by the time the slow down point is reached.

There are other features present in the preferred arrangement for carrying out the invention. According to the preferred arrangement, a plurality of switches are provided for controlling both acceleration and retardation which are operated by means actuated in accordance with movement of the elevator car. In starting the car these switches are closed in a certain sequence as the car reaches points definite distances from the floor from which it started. In slowing down the car, these switches are opened in a reverse sequence as the car reaches points definite distances from the floor at which a stop is being made.

According to the embodiment which will be described, this mechanism is arranged so that the distance of car travel on less than full speed runs is divided in half with the first half allotted to accelerating and the last half to retardation. This is a convenient and preferred arrangement, although it is to be understood that other divisions of the length of the run may be adopted. In this arrangement the switches are closed during acceleration through a member which is actuated in accordance with car movement and at a rate which is in effect twice the rate of car movement. This member continues its advance until it has operated all of the switches .and thereafter it is moved at the same rate as the car. The member is brought to a stop either during its advance or while in advanced position upon its arrival in effect at a point corresponding to the floor at which a stop is to be made.

Continued movement of the car after this memher is brought to a stop efiects the reverse operation of said switches to control retardation of the car. In this way the acceleration and retardation portions of the run are made equal and the switches are opened the same distances from the floor at which a stop is being made as the distances from the floor from which the car was started that the switches were closed during acceleration. The operation of the switches is effected through cams which are actuated in one direction to control acceleration and in the reverse direction to control retardation, regardless of the direction of car movement. The control means for arresting acceleration on short floor runs is carried by the member actuated in accordance with car movement.

It is desirable, especially in installations in which hall lanterns are provided for indicating floors at which stops are to be made, to pick up the calls considerably in advance of the arrival of the car at the stopping floor. By arranging the control system so that the proper hall lantern is lighted as soon as the call is picked up, a long advance lighting of the hall lantern is assured. Thus, especially in cases where a plurality of elevator cars are controlled in a group by hall buttons common to that group, intending passengers at the stopping floors are advised as which car is to make the stop in ample time to reach the entrance for that car by the time the car arrives at the door. In order to provide ample advance lighting of the hall lanterns on short floor runs, the system may be arranged to pick up the call during the closing of the hatchway door and car gate. To effect this operation a movable member, provided with control means for picking out the floors at which stops are to be made, is actuated to an advance position with respect to the car during the closing of the doors and independently of car movement. This control means is arranged to cooperate with stationary control means spaced in accordance with the distance between floors to pick up the calls. After the movable member reaches an advanced position with respect to the car, it is actuated in this advanced position in accordance with movement of the elevator car. This permits a call to be picked up prior to the starting of the car when the car is at a distance rom the floor for which the call is registered in which a full speed run cannot be made and on a full speed run upon the arrival of the car a certain distance from the floor. Thus, by lighting the hall lanterns as soon as the calls are picked up, ample advance notification is given to the intending passengers at the floors of the cars which will make the stops.

In addition to the above features, other features and advantages will become apparent from the following description, with reference to a particular application of the invention, and the appended claims.

In the drawings:

Figure 1 is a simplified schematic representation of an elevator installation embodying a selector machine in accordance with the invention;

Figure 2 is a schematic representation of the selector machine;

Figure 3 is a view of the base plate of the selector machine illustrating particularly the driving arrangement;

Figure 4 is a view of the mechanism mounted on the top plate of the selector machine;

Figure 5 is a sectional view taken between the top and base plates of the selector machine and above the selector machine crossheads;

Figure 6 is an enlarged detail similar to Figure 5 of the selector machine crossheads;

Figure '7 is a side view of the synchronous and distance advance crossheads and the driving arrangement therefor;

Figure 8 is an end view of the same;

Figure 9 is an enlarged detail of switches operated by relative movement of the motor advance and distance advance crossheads;

Figure 10 illustrates the settings of the operating cams for the selector switches;

Figure 11 is a View illustrating the arrangement of the brushes carried by the synchronous and distance advance panels; and

Figure 12 is a similar view illustrating the arrangement of the brushes carried by the motor advance panel.

For a general understanding of a typical elevator installation to which the invention is applicable, reference may be had to Figure 1. An elevator installation has been schematically illustrated in which the car may be controlled as, for example, in the co-pending application of Lewis and Bruns, Serial No. 338,872, filed June 5, 1940. Various parts of the system are indicated by legend. The car is raised and lowered by means of the hoisting motor which drives a traction sheave over which pass hoisting ropes for the car and counterweight. An electromechanical brake is provided and is applied in stopping the car and holding the car when at rest. In the arrangement described in the aforesaid Lewis and Bruns application, current is supplied to the hoisting motor by two generators having their armatures connected in series relation. The two motor generator sets are designated No. 1 MG set and No. 2 MG set. An eXciter set is provided, the exciter supplying the current for certain of the field windings and control apparatus. A terminal stopping switch is mounted on the car and is operated by cams at the terminals which engage a roller mounted on the operating arm of the switch to swing it from one operating position to the other.

The invention is illustrated as applied to a system in which the starting of the car is under the control of an attendant in the car, while stops are made in response to buttons pressed by intending passengers at the landings and by buttons pressed in the car by the attendant under the direction of the passengers. The push buttons at the landings, termed hall buttons, are arranged in push button boxes, an up and a down push button being provided at each intermediate floor and one push button at each terminal floor. The push buttons within the car, termed car buttons, are arranged on a car operating panel. On this panel is also arranged the start control switch.

The selector machine is illustrated as driven from the elevator car by a flexible tape secured at one end to the top of the elevator car and at the other end to a reel upon which it is wound and unwound in the driving operation. This reel is mounted on a shaft connected to the selector drive shaft by a chain. Slack in the tape is taken up by a torque motor, which will be referred to as the tape motor. A tape motor brake is applied when the tape motor is deenergized. Should slack develop in the tape, a slack tape switch, through which the tape is attached to the car, is opened to shut down the system. Mechanism is mounted on the end of the selector drive shaft for operating contacts in accordance with motion of the elevator car and its direction of travel. This mechanism, which is termed a motion device, will not be described in detail.

Reference may now be had to Figure 2, which illustrates schematically a selector machine of preferred construction. This figure is for the purpose of giving a comprehensive understanding of the machine and its operation. It is not intended to show details of construction, such details being illustrated in Figures 3 to 12 inclusive. In the drawings showing details of construction, certain parts not involved in the portion of the mechanism illustrated in any particular figure of drawings are not shown in that figure in order that the construction and operation of the mechanism may be readily understood. For convenience, the selector machine is shown for a five floor installation.

Referring also to Figure 3, the drive tape 30' which winds on and unwinds from reel 3| is secured to this, reel by a pin 32. The reel is secured to a shaft 33 supported in bearing plates 34 mounted on a base 35. This shaft is connected through gears 36 and 31 to the shaft 38 of tape motor TM. Also arranged on this shaft is the brake pulley 41 to which the tape motor brake shoes 42 and 43. shown in section, are applied. The tape motor is energized while the car is in service to exert a torque in a direction tending to wind up the tape on the reel, that is, to turn the reel counterclockwise as viewed from the right in Figure 3. Thus, during upward movement of the car the tape motor winds up the tape on the reel, while during downward movement the tape is unwound from the reel by the car against the torque of the tape motor.

Also secured to shaft 33 is a sprocket wheel 45. This sprocket wheel is connected by sprocket chain 46 to another sprocket wheel 41 secured to selector drive shaft 48. Thus shaft 48 is driven counterclockwise, as viewed in Figure 3, during upward movement of the car. A tensioning sprocket wheel 50 is mounted on an arm r0- tatively mounted on drive shaft 48. The drive shaft is supported by bearing stands 52 mounted on the selector base plate 53. The base plate is connected to the top plate 54 by angle members 55 secured to these plates at the corners (see also Figure 4), thereby forming a frame.

The selector machine has three moving crossheads, indicated in Figure 2. One of these crossheads, designated 56, is driven by means of a motor AM mounted on the top of top plate 54. This crosshead will be termed the motor advance crosshead and the motor the advancer motor. The other two of these crossheads are actuated in accordance with car movement. One of them, designated 58, will be termed the synchronous crosshead and the other, designated 60, being driven in the ratio of 2:1 with respect to the synchronous crosshead, will be termed the distance advance crosshead.

Referring also to Figures 4, 5, 6 and 8, the advancer motor AM operates through reduction gears El, 52, 63 and 64 to drive a sprocket wheel 65. The sprocket wheel and gear 54 are secured to a shaft supported by bearing plates E se-' cured to the base 68 for the motor. Gears 62 and are mounted on another shaft 10, also supported by bearing plates 61, while gear 6| is secured to the end of the motor shaft. The sprocket wheel drives a sprocket chain 7| secured at one end to the top of the motor advance crossdiate floor as a call head 56, from which it extends upwardly and around the sprocket wheel, downwardly through a cylindrical tube 12 extending between the top and bottom plates, thence around an idler sprocket 13 secured to the bottom of the base plate 53 and thence upwardly to the bottom of the motor advance crosshead, to which the other end of the chain is secured. The ends of the chain are secured to the crosshead by adjusting bolts 74 to enable any slack in the chain to be taken up. A counterweight (not shown) for the motor advance crosshead is arranged within tube 72 and connected to the sprocket chain.

The motor advance crosshead is guided in its movement by a rod 15 extending between the top 233 and bottom 234 of the synchronous crosshead 58. This rod extends through apertures in guide members 16 formed on the crosshead. The opposite end of the crosshead is formed with prongs T! to span a bar 18 extending between the top and bottom of the synchronous crosshead, thereby forming a supplementary guide for the motor advance crosshead. Stops Bil and 8!, adjustably mounted on rod 15, limit the movement of the motor advance crosshead with respect to the synchronous crosshead.

The motor advance crosshead carries a frame 82 upon which are mounted a plurality of circuit controlling elements for cooperating with stationary circuit controlling elements mounted on floor bars 83, one for each floor served by the car. These floor bars are spaced in accordance with the distance between the floors for which they are provided and are mounted on rods 84 secured to the bottom and top plates of the selector machine. Each floor bar comprises an elongated flat bar 85 spanning rods 84 and secured thereto by means of angle clamps 86 and screws 81, as shown in Figure 5. The bar is provided with a plurality of spaced apertures utilized in the present arrangement for mounting a plurality of spring contacts. These spring contacts are mounted on the floor bars through insulating bases 88 in the same manner as disclosed in the co-pending application of Edward Lee Dunn, Serial No. 214,271, filed June 17, 1938, in connection with Figure 13 thereof. Also, the construction of the spring contacts is the same as that of spring contact I93 of that application. It is believed, therefore, that these spring contacts need not be further described here.

In the control system of the aforementioned Lewis and Bruns application, one of these spring contacts, designated CP, serves for an intermepick up contact for calls registered by the pressing of the car button for that floor. There is one of these contacts on each floor bar. The next spring contact to the right, as viewed in Figure 5, which is designated PH, serves as a call pick up holding contact. There is one of these contacts on each floor bar. The next spring contact to the right, designated DHP, serves as a down hall call pick up contact. There is one of these contacts on each of the floor bars except the floor bar for the upper terminal floor. The next spring contact to the right, designated UI-IP, serves as an up hall call pick up contact. There is one of these contacts on each of the floor bars except the floor bar for the lower terminal floor. The last spring contact, designated AP, serves as an auxiliary preretardation control contact. There is one of these contacts on each floor bar,

The crosshead frame 82, which carries the various elements for contacting with the spring,

contacts above described, is secured to the cross head by means of strap 90 and angle 9i. The frame is provided with a mounting panel for the contacting elements. Referring also to Figure 12, this panel, which is of insulating material, is arranged in duplicate sections 92 secured to the frame in abutting relationship. This panel will hereinafter be referred to as the motor advance panel. The various contacts cooperating with the spring contacts on the floor bars are secured to brackets adjustably mounted in slots in the panels. This arrangement is the same as that described in the aforementioned co-pending Dunn application, and will not be further described. The contact for engaging spring contacts CP is designated CPB and serves as the car call pick up brush. The contact for cooperating with spring contacts PH is designated PHB and serves as the call pick up holding brush. This brush is a relatively long one as compared with brush CPB. The brushes for cooperating with spring contacts DHP and UHF are designated DHB and UHB respectively, these contacts serving as the down hall call pick up brush and the up hall call pick up brush respectively. These brushes also are relatively long and each is divided into a leading section 93 and a trailing section 94. The contact for cooperating with spring contacts AP is designated APB and serves as the auxiliary pre-retardation control brush. This brush also is a relatively long brush.

The motor advance crosshead also carries a pair of switches (see Figure 9), one effective for upward movement of the crosshead and the other for downward movement. The up motor advance switch, designated MAU, extends upwardly from the crosshead, while the down motor advance switch, designated MAD, extends downwardly from the crosshead. These switches are mounted on a mounting plate 95 secured to the crosshead. Each of these switches is of the same construction which is described in the aforementioned co-pending Dunn application wherein the switches are shown in Figures 10 and 14.

Each switch comprises a frame 96 of molded insulating material. secured to the mounting plate. A pair of leaf springs 91 is secured by terminal screws to the frame. Protecting steps 98 are formed on each side of the frame, between which the contact springs extend. The movable contact comprises a lever I pivotally mounted on a pin supported on the frame and having its upper end IOI bent toward the contact springs. A bridging member in the form of an angle I02 is secured to the bent end of the lever. The lever is biased by a spring I04 to a position where member I02 bridges the contact tips of the contact springs. The lever is channel shaped and lugs are formed on the sides of the channel to form a support for the pivot pin of operating roller I05. This roller is positioned in the path of movement of cam I06 secured to distance advance panel 60, the arrangement being such that with the car stopped at the floor the rollers of both switches are engaged, causing these switches to be open.

Reference may now be had to Figures 2, 5, 6, 7 and 8. The distance advance crosshead 60 is guided in its movement on the cylindrical tube 12 and on another cylindrical tube IIO, also extending between the top and base plates of the selector. An aperture III is provided in the crosshead through which tube I2 extends. Guide shoes IIZ engage tube IIO, these guide shoes being held in place by screws I01 extending through arms I08 and I09 formed by bifurcating the crosshead, the screws being held in position by lock nuts.

The distance advance crosshead carries a pair of oppositely disposed pawls H3 and H4 for cooperating with stopping lugs H5 mounted on an elongated rod I I6. Each pawl is pivotally mounted on a pivot pin IIl extending from a bracket II9 secured to the crosshead. Each pawl is provided with a spring [I8 for biasing it into position for cooperation with the stopping lugs. Lug I20 formed on each pawl cooperates with bracket [I9 to limit the outward movement of the pawl.

The stopping lugs II5 are carried by collars I2I adjustably mounted on rod H6. A stopping lug is provided for each floor, the collars being in spaced relation on rod I It in accordance with the distance between the floors for which they are provided. The collars are split to permit adjustment and clamping thereof to the rod, the collars being clamped in adjusted positions by bolts I22. Each stopping lug is provided with a threaded stem I23 which extends through an aperture I24 in supporting arm I25 formed on the collar. A shoulder I20 is formed on this arm, against which the lug fits to prevent rotative movement thereof. The lug is clamped in its proper position by means of a nut I21 on the threaded end of the stem.

The stopping lugs are retracted during movement of the crosshead into position where the pawls clear the lugs. The lugs are maintained retracted until the car arrives at a certain distance from the landing at which a stop is to be made. When this condition is reached, the lugs are released and move into position for cooperation with the pawls. This operation is controlled by an electromagnet, termed the pawl magnet and designated SM, mounted on the bottom of top plate 54. This magnet, as shown in Figures 2 and 4, operates a lever I 28 pivotally connected to the movable core I30 which extends into the magnet through an aperture I3I in the magnet frame I32. The lever is biased to unattractecl position by a spring I 33 arranged between the lever and the magnet frame. A screw I29 adjustably mounted on the other end of the lever engages an abutment I39 extending between the top and bottom plates of the magnet frame to limit the movement of the lever by spring I33. The lever is formed on a sleeve I34 secured as by a pin to a pivot shaft I35 rotatably mounted in the top and bottom plates I35 of the magnet frame. The pivot shaft extends below the magnet frame, where it is secured by bolt I31 to the rod H5, the rod in turn being pivoted in the base plate 53 of the selector.

A bar I38 secured to lever I28 controls the operation of pawl magnet switch SMI. This switch, which is of the same construction as the switch shown in Figure 9, is pivotally mounted on selector top plate 54 and is biased by spring I40 to closed position. Operating roller MI oi the switch is engaged by bar I38 when the pawl magnet; is deenergized to maintain the switch in open position against the force of spring I40.

Upon energization of the pawl magnet its movable core is pulled inwardly or clockwise as viewed in Figure 2, causing clockwise rotative movement of lever I28. This moves bar I38 away from roller Ill, permitting spring I43 to close switch SMI. It also rotates rod I15 clockwise, which retracts the stopping lugs into position where they are clear of the pawls. When this has been done, the distance advance crosshead is free to move.

The distance advance crosshead is driven from the selector drive shaft 48 through the intermediary of a sprocket chain I42. This chain is driven by a sprocket wheel I43 which is secured to a shaft I44. As shown in Figure 3, this shaft is supported by bearings stands I45 mounted on selector base plate 53. The shaft is driven by a bevelled gear I46 secured to the shaft, this gear in turn being driven by a small bevelled gear I41 secured to selector drive shaft 48. Thus sprocket wheel I43 is driven clockwise, as viewed in Figure 2, during upward car movement and counterclockwise during downward car movement.

Sprocket chain I42 is an endless chain extending upwardly from sprocket wheel I43 around an idler sprocket wheel I48 above the top plate of the selector. This wheel is rotatably mounted on lever I50, in turn pivoted tobracket I I secured to top plate 54. The opposite end of the lever is held between two nuts arranged on an adjusting screw I52 secured to top plate 54, this arrangement being provided to take up any slack in the chain. v

Chain I42 engages a sprocket wheel I55 pivotally mounted on a stub shaft I56 secured to a plate I51 which, in turn, is secured to distance advance crosshead 60, as shown in Figures 6, '1 and 8. A bushing I58 is provided in an aperture in the sprocket wheel to form a bearing. The chain is maintained in meshing relationship with the sprocket by a shoe I60 secured to plate I51. A clutch device I6I is provided to hold sprocket I55 against rotative movement with respect to stub shaft I56. This clutch comprises two discs I62 and I63 with a ring I 64 of brake lining material arranged between them. The inner disc I62 is secured as by screws to the the sprocket Wheel I55. It is provided with an annular shoulder I65 to locate the ring I64. The outer disc I63 is formed with a pair of lugs I66 which straddle a pin I61 secured to plate I51. This prevents the rotative movement of disc I 63' with respect to stub shaft I56, while allowing linear movement of the disc on the shaft. The discs and ring are pressed together by the spring I68 arranged on the stub shaft between a spring seat I10 and a boss "I formed on disc I63. A cotter pin I12 holds spring seat I10 in position to maintain spring I 68 in a state of compression. With this arrangement, upon movement of sprocket chain I42, rotation of sprocket wheel I55 is prevented by the clutch device so that the distance advance crosshead 60 is carried along with sprocket chain I42 in accordance with movement of the elevator car.

As shown in Figure 2, a chain I15 is adjustably secured at one end to the top of distance advance crosshead 60, from which it extends upwardly to and around an idler pulley I16 pivotally mounted on a bracket I11 secured to top plate 54. From this pulley, the chain extends downwardly through cylindrical tube IIO to and around another idler pulley I18 pivotally mounted on a bracket I80 secured to the bottom of base plate 53 and thence upwardly to the bottom of crosshead 60 to which the other end is adjustably secured. A counterweight (not shown) for the distance advance crosshead is provided within tube III] and connected to this sprocket chain.

The distance advance crosshead carries a frame I82 similar to frame 82 and carrying a plurality of circuit controlling elements for cooperating with stationary circuit controlling elements on floor bars I83, one for each floor served by the car. These floor bars are spaced in accordance with the distance between the floors for which they are provided and are mounted on rods I84 secured to the bottom and top plates of the selector machine. These floor bars are of the same construction and are secured in the same Way to the rods as floor bars 83. Also, spring contacts are mounted on these floor bars the same as on floor bars 83. Four spring, contacts are arranged on each floor bar (see Figure 5). Two of these contacts are of the same construction as spring contact I93 of the aforementioned co-pending Dunn application. The other two contacts are arranged for mutual cooperation and are of the same con-- structicn as spring contacts I86 and I81 of the aforementioned co-pending Dunn application. In the control system of the aforementioned Lewis and Bruns application, the spring contact designated IPR serves as the first preretardation control contact for the floor for which it is provided. The spring contact designated ZPR serves as the second pre-retardation control contact for the floor for which it is provided. The remaining mutually cooperating spring contacts, which are designated AS, serve as auxiliary starting relay control contacts for the particular floor for which they are provided.

The crosshead frame I82 which carries the elements contacting with the spring contacts just referred to is secured to the distance advance crosshead by means of straps I90 and is provided with a panel hereinafter termed the distance advance panel. Referring to Figure 11, this panel, as in the case of the motor advance panel, is arranged in duplicate sections I62 in abutting relationship. The contacts are mounted on these sections the same as the contactson section 92. Two spaced contacts are provided for engaging spring contacts IPR, one effective for up car travel and one effective for down car travel. The up contact is designated IUPB and serves as the first up pre-retardation brush. The down contact is designated IDPB and serves as the first down pre-retardation brush. Two spaced contacts are provided for engaging spring contacts ZPR, one effective for up car travel and one effective for down car travel. The up contact is designated 2UPB and serves as the second up pre-retardation brush. The down contact is designated ZDPB and serves as the second down pre-retardation brush. One of the spring contacts AS for each floor is provided with an outer contact tip which is engaged by an elongated contact designated ASB mounted on one of panel sections I92. This contact serves as the auxiliary starting relay control brush.

Sprocket wheel I55 meshes with another sprocket chain I93 arranged on the side of the sprocket wheel opposite from chain I42. Chain I93 is maintained in meshing relationship with the sprocket by shoe I94 secured to plate I51. The chain is an endless one, extending around sprocket wheels I95 and I96 at the top and bottom respectively of the selector machine. Sprocket wheel I96 is rotatably mounted on lever I91, in turn pivoted to bracket I98 secured to base plate 53. The opposite end of the lever is held between two nuts arranged on an adjusting screw 290 secured to base plate 53, this arrangement being j provided to take up any slack in the chain.

Referring to Figure 4, sprocket wheel I65 at the top of the selector is mounted on a shaft 202 rotatably supported in bearing stands 203 and 204 provided on base 205 secured to top plate 54. Ratio gears 206 and 201 are provided for transmitting the rotation of shaft 2t2 to another shaft 208 also supported in bearing stands 203 and 204, gear 200 being secured to shaft 202 and gear 2M being secured to shaft 208. Arranged on the other end of shaft 208 beyond bearing stand 204 is a uniform motion cam 2I0, the contour of which is shown in Figure 2. This cam is arranged to effect linear movement of a frame 2| I through the intermediary of rollers 2I4 and 2I5 pivotally mounted on the frame. This frame slides on a rod 2I2 secured to bearing stand 204. The frame comprises two side plates connected by yokes 2I3. These yokes are provided with apertures through which rod 2I2 extends. A screw 2I9, extending through a slot in one of the side plates and secured to stand 204, prevents the frame from turning on the rod. The rollers are mounted on stub shafts 2I6 and 2H secured to frame 2I I. Stub shaft 2I6 has an extension 2I0, which is to be engaged by stop member 220 secured to cam 2I0 to bring the cam to a stop, upon its rotation in either direction from the neutral position illustrated in Figure 2 through an angle slightly less than 180.

With this arrangement, movement of distance advance crosshead 60 by chain I42 causes movement of chain I93 along with the crosshead. This causes rotation of cam 2 I through sprocket wheel I95 and ratio gears 206 and in a direction from neutral depending upon the direction of movement of the distance advance crosshead. Upon the engagement of stop member 220 with extension 2 I8, cam 21 I is brought to a stop, which brings chain I93 to a stop. Continued movement of chain I42 causes sprocket wheel I55 to roll on chain I93 as a rack, clutch IBI yielding to permit rotation of sprocket wheel I55 on shaft I56. Thus, after movement of chain I93 is stopped by the engagement of stop member 220 with extension 2I0, continued movement of the distance advance crosshead takes place at half the speed of chain I42 instead of the same speed as it did prior to the stopping of chain I53.

Uniform motion cam 2I0 is utilized to effect the operation of a plurality of switches arranged on the top of the selector machine. A rack 22I is secured to frame 2II so as to move linearly therewith. This rack engages a pinion 222 arranged on a cross shaft 223 supported by bearing stands 224 and 225 secured to top plate 54. The

switches are operated by cams arranged on the cross shaft to be operated by the rack and pinion. These switches are mounted in spaced relationship on a cross bar 226 extending between and supported by bearing stands 224 and 225. The switches are of the same construction as that illustrated in Figure 9, seven of them being provided with making contacts and four of them with breaking contacts. These switches are principally for controlling acceleration and retardation of the elevator car and will hereinafter be referred to as selector switches.

By effecting rotative movement of shaft 223 upon which the operating cams for the selector switches are mounted, by a uniform motion cam, the motion of shaft 223 is effected in direct proportion to the movement of the distance advance crosshead and therefore to the movement of the elevator car. Also, shaft 223 is rotated in the same direction by this cam during its movement from neutral position, regardless of the direction switch of rotation of the cam and therefore regardless of the direction of travel of the car. The size of pinion 222 is chosen so that shaft 223 rotates at twice the speed of shaft 208. Thus nearly a full revolution of shaft 223 is effected before the uniform motion cam is brought to a stop. This is an advantage in setting the operation of the selector switches. Also, with this arrangement cams of uniform construction can be employed for operating all the switches. A pair of cams 228 are provided for each switch, these cams being arranged on shaft 223 in position to engage the operating rollers of the switches for which the cams are provided. Each cam is a 180 cam, provided with a split hub, a screw extending across the split portion of the hub being provided to clamp the cam to the shaft. Inasmuch as haft 223 is rotated in the same direction for each direction of car travel, a correct setting of each cam for one direction of car movement is correct for the opposite direction of movement.

In the control system of the aforementioned Lewis and Bruns application, only a certain number of the selector switches which may be provided on the top of the selector are utilized. A sequence diagram for the switches utilized is indicated in Figure 10. Each of these switches is designated by the letters SS with a numeral appended thereto to differentiate between them. These switches, being operated in accordance with the movement of the elevator car, are operated when the car reaches points certain distances from the floor as the car leaves that floor in starting. These distances are determined by the setting of the cams, in turn determined by the particular control operations performed. As will be shown later, reverse operation of these switches takes place during stopping of the car at a floor as the car reaches points the same distances from this floor as the distances of the points at which these switches operated during starting from the floor from which the car started.

Selector switches SS3, SS4 and SS5 control the acceleration of the car while these switches and switches SSI and SS2 control retardation. Switch SS1 controls the operation of the brake under certain conditions. Switches SS8 and SS9 control the effectiveness of the first and second pre-retardation brushes. Switch SSII controls the automatic opening of the hatchway door and car gate in stopping. Switch SSIZ controls initiation of slow down from a full speed run. Switch SSI3 controls the circuits for certain of the accelerating switches. The actual setting of the switches is determined by the particular installation. In the control system illustrated in the aforementioned Lewis and Bruns application, it has been found that for certain apparatus and a full speed of 800 feet per minute the cams may be setto operate their switches substantially as follows: switch SSI upon 6 of rotative movement of the operating cams out of neutral; switch SS2 upon 27 of rotative movement; SS3 upon 43 of rotative movement; SS4 upon of rotative movement; SS5 upon 186 of rotative movement; SS1 upon 1 of rotative movement; SSO upon 28 of rotative movement; SS9 upon 75 of rotative movement; switch SSII upon 18 of rotative movement; switch SSI2 upon 308 of rotative movement; and switch SSI3 upon 10 of rotative movement. The uniform motion cam is brought to a stop after approximately 315 of rotative movement switch switch switch switch switch of the cams. For 800 feet per minute full operating speed of the car, this 315 movement of the cams is effected in 25 feet of car travel, the ratio of gears 206 and 201 being chosen so that for a given size sprocket wheel I95 this relationship is obtained.

The distance advance crosshead carries cam members 239 and NI for operating switches carried by the synchronous crosshead 58. These cam members are secured to the top and bottom of frame I82. The switches operated by these cam members are of the same construction as those illustrated in Figure 9 and therefore will not be described. One of these switches is effective for upward movement of the distance advance crosshead and the other for downward movement. These switches will be hereinafter referred to as up distance advance switch DAU and down distance advance switch DAD. These switches are mounted on the panel mounting frame 232 carried by the synchronous crosshead.

The synchronous crosshead comprises an upper cross member 233 and a lower cross member 234 joined by side members 235 and 236. This crosshead is guided by the cylindrical members l2 and H2, an aperture 23'! being provided in the top member of the crosshead and another aperture 238 being provided in the bottom member of the crosshead to receive cylindrical member l2. Both the top member and the bottom member of the crosshead are provided with guide shoes 240 for engaging tube IIU, these guide shoes for each member being held in place by screws 24I extending through arms 242 and 243 formed by bifurcating this portion of the crosshead, the screws being held in position by lock nuts 244. Side member 236 is in the form of a channel and is secured to the arms 242 and 243 of the top and bottom members. The guide rod I5 for the motor advance crosshead is secured in lugs 245 formed on the top and bottom members of the synchronous crosshead. The guide bar 18 for the motor advance crosshead is secured in lugs 24% formed on the top and bottom members of the synchronous crosshead.

Side member 235 of the synchronous crosshead is in the form of a plate extending from the top and bottom members of the synchronous crosshead. The frame 232 is secured to this plate by means of a strap 241. Spring contacts of the same construction as spring contacts CP are mounted on floor bars I83. In the control system of the aforementioned Lewis and Bruns application, one of these contacts serves to control certain levelling operations upon an overrun and is designated OV. There is one of these contacts for each floor. The other spring contact controls direction and is designated CD, these contacts being provided only on the floor bars for the terminal floors. These spring contacts are adapted to be engaged by contacts mounted on duplicate panel sections 249 secured to frame 232. The contact for engaging spring contacts 0V is designated OVB, while the contact for engaging spring contacts CD is designated CDB.

The synchronous crosshead is driven by chain I42, A sprocket wheel 25!? is secured to a jack shaft 25I rotatably supported in the bottom member 234 of the crosshead. This sprocket wheel meshes with the left hand run of the chain, a shoe 252 being secured to the bottom member of the crosshead in position to maintain the chain in meshing relationship with the sprocket wheel. Secured to the other end of shaft 25I is a similar sprocket wheel 253. On the right hand side as viewed in Figure 2, this sprocket wheel meshes with a stationary chain 254, a shoe 255 being secured to the bottom member of the crosshead in position to maintain the chain in meshin relationship with the sprocket wheel. This chain is secured to and extends between base plate 53 and top plate 54 of the selector, adjusting screws 255 being provided to secure the chain to the plates. With this arrangement, upon movement of drive chain I 42, sprocket wheel 253 is driven through sprocket wheel 25!] and shaft 25f, causing it to roll on stationary chain 254 as a rack. This movement occurs in the same direction as the movement of the left hand run of chain I42 as viewed in Figure 2, but at one-half the speed. The floor bars, as previously pointed out, are spaced in accordance with the distances between the floors for which they are provided. The setting of the floor bars is in accordance with the ratio of the movement of the synchronous panel with respect to the movement of the elevator car. Thus, from the standpoint of the setting of the floor bars, the distance advance crosshead initially moves at twice the speed of the elevator car until stop member 220 on the uniform motion cam 2I0 engages extension 2I8 of the stub shaft 2I6. From then on, due to the slipping of clutch device I6I, the distance advance panel moves at the same speed as the elevator car, in unison with the synchronous panel.

When the car is stopped at a floor all the crossheads and therefore all the panels are in neutral position with respect to the floor bar for the floor at which the car is stopped. In the control system illustrated in the aforementioned Lewis and Bruns application, in starting the car, the advancer motor is energized, prior to the starting of the car, to move the motor advance panel upwardly if the car is being started in the up direction, and downwardly if the car is being started in the down direction. Movement of the motor advance panel takes place rapidly. During the initial movement of the motor advance panel, the motor advance switch for the corresponding direction of travel is closed by the disengagement of its operating roller from cam I06. If the car is being started in the up direction switch MAU is closed and if the car is being started in the down direction switch MAD is closed. The closing of either switch causes the energization of pawl magnet SM to retract the stopping lugs, which frees the distance advance panel for movement, Upon the motor advance crosshead engaging its stopping collar, the advance of the motor advance panel is discontinued. This preferably takes place before the car is actually started.

As the car starts, the synchronous panel and the distance advance panel are both moved in the direction in which the car is started, the synchronous panel moving in accordance with the speed of the elevator car with respect to the floor bars and the distance advance panel moving at twice car speed with respect to the floor bars. Movement of the synchronous panel permits movement of the motor advance panel to keep the motor advance crosshead against its stop. As relative movement of the distance advance and synchronous panels takes place, distance advance switch DAU or DAD for the direction in which the car is moving is closed by the disengagement of its operating roller from cam member 230 or 23I respectively. Movement of the distance advance crosshead causes operation of the selector switches in sequence, thereby controlling the acceleration of the car in accordance with the distance the car moves. Assuming that a run is to be made which will permit the car to attain full speed, the distance advance panel continues its advance with respect to the synchronous panel until fully advanced, whereupon relative movement between the distance advance panel and the synchronous panel is stopped by the engagement of stop member 220 with extension 2 l From this point on until a call is picked up, the three panels move as a unit at the same speed.

When a call is picked up the advancer motor is deenergized. A call is picked up by the engagement of brush CPB with an alive one of contacts CT or by the engagement of up brush UHB during up car travel or down brush DI-IB during down car travel with an alive one of its cooperating stationary contacts. When the advancer motor becomes deenergized, the motor advance panel comes to a stop. This takes place very quickly, so that the motor advance panel comes to rest in neutral position with respect to the floor bar for the floor for which the call is picked up and the brushes on the panel are maintained in engagement with the contacts for the floor for which the call is picked up. The distance advance panel and synchronous panel continue to move in accordance with car move ment, catching up with the motor advance panel.

J ust before the distance advance panel catches up with the motor advance panel, the operated motor advance switch MAU or MAD is opened, which causes the deenergization of pawl magnet SM. This releases the stopping lugs H5 to extend them into the path of movement of the pawls. The stopping lug for the floor for which the call hase been picked up is thereupon engaged by the pawl for the direction in which the car is travelling, pawl H3 serving as the up pawl and pawl IN serving as the down pawl. This brings the distance advance crosshead to a stop. This is in neutral position with respect to the floor bar for the floor at which the stop is to be made, at which time the auxiliary starting relay control contacts AS for that floor are opened by their brush ASE.

Inasmuch as the car continues in motion after the distance advance crosshead is brought to a stop, chain I42 continues to drive the synchronous crosshead in accordance with movement of the elevator car. Owing to the fact that the distance advance crosshead is stopped, chain I42 also acts to rotate sprocket wheel 155 counterclockwise as viewed in Figure 2 in case of up car travel and clockwise in case of down car travel, clutch device l6! yielding to permit this rotative movement. In doing so, sprocket wheel 155 drives the right hand run of chain downwardly in case of up car travel and upwardly in case of down car travel. Considered from the standpoint of distance between floor bars, this occurs at twice the speed of the elevator car. Thus as the car continues its movement, the operated cams for the selector switches are gradually returned to neutral position, causing restoration of the selector switches to their former positions at distances from the floor at which the stop is being made corresponding to the distances from the floor from which the car was started that these switches were respectively operated. This causes the car to be slowed down, providing distance control of the retardation of the car. The

final stopping of the car at the floor is controlled by the levelling mechanism, which will be described later. Just before the car reaches the iioor, selector switch SSH opens to cause the opening of the car gate and hatchway door. During this slow down operation, the synchronous crosshead, continuing its movement, gradually catches up with the distance advance and motor advance crossheads. Just before the car comes to a stop the operated distance switch DAU or DAD is opened. When the car is brought to a stop at the floor the synchronous crosshead also stops, this occurring with the synchronous panel in neutral position with respect to the floor bar for the floor at which the stop is being made.

It may happen that a call is picked up by a brush on the motor advance panel before this panel reaches fully advanced position. Under such circumstances the advancer motor is immediately deenergized, bringing the motor advance panel to a stop with its brushes in engagement with the stationary contacts for the floor for which the call is picked up. Upon the car being started, the synchronous panel and distance ad- Vance panel are moved by the car in the same manner as on the full speed run above described. However, when making a short floor run, the pre-retardation brushes P18, in cooperation with their respective stationary contacts for the floor for which the call is picked up, the effective preretardation brush being dependent upon the direction of car travel and the length of the run, act in advance of the point at which slow down begins to decrease the rate of acceleration. Just before the distance advance panel catches up with the motor advance panel, operated switch MAU or MAD opens. causing cleenergization of the pawl magnet SM. The stopping lugs are released and the lug for the floor for which the call is picked up is engaged by the pawl for the direction in which the car is travelling. This causes reverse operation of the operated selector switches to slow down the car and finally bring it to a stop at the floor for which the call has been picked up. Thus on a short floor run as well as a full speed run distance control of acceleration and retardation is provided.

Reference may now be had to Figures 2, 4 and 5, which illustrate the mechanism for bringing the car to an exact landing level. This levelling mechanism is illustrated as arranged on the selector machine. The synchronous crosshead 58 carries a frame 250. The top and bottom members 26] and 262 of the frame are provided with vertically aligned apertures 263 to receive tubular members 264 and 265. These tubular members are rotatably mounted in the apertures, bushings (not shown) being provided in the apertures to form bearings for the tubular members. Sleeves 266 and 261 are secured as by screws 258 to tubular members 254 and 2&5 respectively. These sleeves are positioned between the top and bottom members of frame 2E0, thereby holding the tubular members in definite positions vertically with respect to the frame. The tubular members are arranged to slide vertically on square rods 263 and 259 extending between the top and base plates of the selector machine. These rods are rotatably supported in bearings provided in the base plate 53 and are likewise rotatably supported at the top through extension members which will be described later. Although the tubular members slide upon the rods as movement of the synchronous crosshead takes place, they cannot turn with respect to the rods, so

that any pivotal movement of these members is imparted to the rods and any pivotal movement of the rods is in turn imparted to the tubular members.

Secured to bottom member 262 of the frame 260 is a bracket 210. This bracket extends downwardly from the frame and has mounted thereon eight switches arranged in columns of four each. These switches are of the same type as those illustrated in Figure 9, three of them in each column being spring biased to contact engaging position and the other in each column being biased into position with the contacts separated. The switches in the left hand column as viewed in Figure 2, designated LIU, L2U, L SU and L3U, serve as up levelling switches, while those in the right hand column, designated LID, L2D, mm and L3D, serve as down levelling switches. Each of the up levelling switches is provided with an operating cam 2'II adjustably clamped to the tubular member 264. Each of the down levelling switches is provided with an operating cam 212 adjustably clamped to the tubular member 265. Each of these cams is of the same construction and comprises a lever 213 having a cam formation 214 on its outer end for engaging the operating roller 275 of the switch for which it is provided. The inner end of the lever and a yoke member 216 form a split hub which is clamped to the tubular member by screws 21?.

Rotative movement of the tubular members to operate the levelling switches during the levelling operation is effected by operating arms 218 and 280 formed on sleeve members 266 and 26'! respectively. Each arm is provided with a roller 28I at its outer end, this roller being supported by roller carrier 282 secured to the end of the arm by a screw 283. These operating arms are operated by a plurality of cams 284, one for each floor. These cams are arranged in spaced relation on a vertical shaft 285. This shaft is rotatably supported at its lower end by thrust bearing 286 arranged in bearing stand 287 secured to base plate 53. At the top this shaft is similarly supported in a bearing 2%, the housing for which is secured to the top plate 54. This shaft is driven by shaft 46 through bevelled gears 290 and 29I, gear 290 being pinned to shaft 48 and gear 29I being pinned to shaft 285.

The cams are spaced along the cam shaft so that the distances between adjacent cams are in accordance with the distances between the respective fioor landings considered from the standpoint of travel of the synchronous crosshead 58. These cams are all similar in construction and each comprises a cam portion 292 and a yoke portion 293. Screws 289 extend through apertures in the yoke portion and are threaded into the cam portion to bind the cam to the cam shaft. The cam portion forms substantially a 180 cam. The radius of the working face 294 of each cam is a maximum at the central portion thereof and a minimum at the end portions. The end portions are bevelled at 295. Each of the cams is helical and has a pitch equal to the travel of the synchronous crosshead per revolution of the cam shaft. Each cam is set radially so that when the car is at rest at the floor for which the cam is provided, the operating rollers 28! on the ends of operating 2'58 and 286 are at points immediately adjacent the end portions 295 of the cam. As will be seen from later description, these rollers are disengaged from the effective surface of the cam at this time.

The operating cams 2H and 212 for the levelling switches are set on the tubular members 264 and 265 respectively so as to cause, under these conditions, the contacts of levelling switch LIU, L2U, L4U, LID, LED and L4D to be separated and the contacts of levelling switches L3U and L3D to be engaged.

When the car is to be started, the square rod 2&8 is rotated counterclockwise and square rod 269 is rotated clockwise as viewed in Figure 2 to move the operating arms 218 and 280 into positions where the operating rollers carried thereby are clear of the levelling cams durin operation of the car. The amount of this movement is sufiicient to move the operating cams 2H and 272 for the up and down levelling switches respectively into positions to permit the closing of levelling switches LlU, LZU, L IU, LID, LZD and L lD by their springs and the opening of levelling switches L3U and L3D by their springs. This movement of rods 268 and 269 is effected by the levelling magnet LEV.

The levelling magnet comprises a coil 296 mounted in a frame 297 secured beneath top plate 54 of the selector machine. This coil is arranged on a non-magnetic sleeve (not shown) held between the side plates 298 of the frame. The magnet is provided with movable cores 300 and 3M. These cores are provided with telescopic ends and extend into the magnet coil. The outer ends of the cores are pivotally connected by links 302 to the arms 303 of the levers 384 and 305 for cores 3% and dill respectively. These levers are secured to shafts 3B6 pivotally mounted in bearings provided in top plate 219 and bottom plate 299 of frame 291. The lower ends of these shafts are connected by bolts 30! to the upper ends of the square rods 268 and 268, these shafts forming the upper extensions of these rods and thereb providing pivotal support for the upper ends. Each of the levers is provided with a spring 368 for biasin the lever against the attraction of the levelling magnet for the movable cores. Adjustable stops SID are provided on the ends of the other arms 3H 0f the levers. These stops engage an abutment 3| 2 secured between the top and bottom plates of the magnet frame to limit the movement of the levers by their biasing springs.

When the car is at rest at a floor, the coil of the levelling magnet is not energized. Under such conditions, springs 368 hold levers 304 and 365 in positions with their stops in engagement with abutment 3E2. As a consequence, square rods 268 and 259 are held in positions with the operating rollers 281 on arms 278 and 280 in non-retracted positions, that is, at points immediately adjacent end portions 295 of the cam for the fioor at which the car is positioned, but slightly disengaged therefrom. As previously pointed out, under such conditions the contacts of levelling switches LiU, L2U, LAU, LID, LZD and LAD are separated and the contacts of levelling switches LBU and L3D are engaged.

The coil of the levelling magnet is energized upon the establishment of circuits incident to the starting of the car. Upon being energized, the levelling magnet acts to pull its cores 306 and 3m inwardly. This causes counterclockwise movement of square rod 268 and clockwise movement of square rod 2% as viewed in Figure 2, moving operating arms 278 and 280 into retracted positions, that is, where the operating rollers 28I carried thereby are clear of the levelling cams. The square rods also act through tubular members 264 and 265 to move operating cams 2H and 212 for the up and down levelling switches respectively into positions where the contacts of levelling switches LIU, LEU, L-tU, LID, L2D and L4D engage and the contacts of levelling switches L3U and L3D separate.

As movement of the car takes place, the operating arms 21B and 280 are moved by the synchronous crosshead in accordance with movement of the elevator car. Also, the levelling cams are rotated by shaft 285 in accordance with the movement of the car. The rollers ZBI on the ends of arms 21!] and 280 clear the cams for the floors at which no stops are made as they run by these cams. However, they are released for cooperation with the cam for the floor at which a stop is being made. When the car reaches a certain distance from such floor, the levelling magnet is deenergized. Springs 366 thereupon act to effect opposite movement of square rods 268 and 269, moving operating arm 2T3 clock-- wise and operating arm 280 counterclockwise as viewed in Figure 2. Assuming upward travel of the car, for example, deenergization of the levelling magnet occurs at such point that the roller on the end of up operating arm 218 engages the portion of the working face of the levelling cam for the floor at which the stop is being made which is of maximum radius. The roller on the end of the down operating arm 23!], however, is not opposite the working face of the cam, so that it does not strike the cam, rotative movement of this arm being stopped by the engagement of adjustable stop 3| l on lever 305 with abutment 3|2. As a result, the contacts of up levelling switches LIU, LZU and LdU are maintained engaged and those of up levelling switch L3U are maintained separated. The contacts of down levelling switches LID, LZD and LAD, however, separate and those of down levelling switch L31) engage.

As the car arrives at a point still closer to the floor, the levelling cam reaches a position with respect to the roller on up arm 218 which permits the opening of levelling switch LIU. Just before the car arrives at the floor, the cam reaches a point which permits the openin of levelling switches LZU and L4H and the closing of levelling switch L3U. The operation of the levelling switches above described controls the operation of the car to bring it to a stop level with the landing. Should the car overrun the floor, the cam runs onto the roller on the end of down operating arm 22!], causing the opening or levelling switch L3D and the closing of levelling switches L4D and LED. This controls the operation of the car to return it to the landing. Just before it arrives at the landing, the levelling cam runs off the down roller, effecting the reopening of switches L lD and LID and the closing of switch L3D. This brings the car to a stop.

The selector machine has been described with special reference to the aforementioned applica tion of Lewis and Bruns, Serial No. 338,872, filed June 5, 1940, which embodies a disclosure of the selector machine as applied to a particular control of an elevator car. Stationary con tacts and cooperating brushes for controlling the lighting of the hall lanterns are not shown in such application but the brushes would be provided on the motor advance panel to obtain long light advance.

It is to be understood that the selector machine is not limited in its application to the particu lar circuits shown in the aforementioned Lewis and Bruns application or to the particular control disclosed therein. The invention is applicable to various types of control systems and the arrangement of the contacts on the panels and cross bars depends upon the particular control system to which the invention is applied. Also, some of the features of the invention may be utilized in certain control systems and not in others. In certain instances the synchronous crosshead may be omitted and the brushes which otherwise would have been carried thereby, if provided, placed on the distance advance panel. Also, in certain instances, especially where hall lanterns are not provided, the motor advance crosshead may be omitted and any brushes which otherwise would have been carried thereby, placed on the distance advance crosshead. Also, various parts of the selector machine may be arranged as separate units if desired. Details of the construction of the embodiment described may be considerably modified. The distance advance crosshead may be operated at a rate with respect to the floor bars at some other multiple of the speed of the car and the acceleration and retardation portions of a short floor run may be divided in some ratio other than half and half.

It is not intended to enumerate all the variations which may be made, as many other than those mentioned may be effected without departing from the spirit and scope of the invention. Therefore it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. Control mechanism for an elevator car comprising, a plurality of switches for controlling acceleration of the car, and means dependent on car movement during starting of the car from a floor at which it was stopped for successively operating said switches respectively at points increasing predetermined distances from such floor as the car reaches such points to increase the speed of the car.

2. Control mechanism for an elevator car comprising, a movable member, means for moving said movable member during starting of the car at a rate which is a certain proportion to the rate of car movement, a plurality of switches for controlling acceleration of the car, and means actuated by said movable member during said movement thereof for operating said switches in sequence.

3. Control mechanism for an elevator car comprising, a movable member, means for moving said movable member in accordance with car movement and at a rate which is a certain pro portion to the rate of car movement, a second movable member, means for moving said second member in accordance with car movement in the same direction as the first movable member and at a rate which is greater than said certain proportion until it has advanced during starting of the car a certain amount with respect to said first movable member, a plurality of switches for controlling acceleration of the car, and means operable by said second movable member during said advance thereof for operating said switches.

4. Control mechanism for an elevator car comprising, a plurality of stationary members, one for each of a plurality of floors, spaced in accordance with the distance between the floors for which they are provided, a movable member, means operable by car movement for moving said movable member with respect to said stationary members at a rate which is a certain proportion to the rate of car movement to advance said member during starting of the car a certain amount with respect to the car, a plurality of switches for controlling acceleration of the car, and means operable by said movable member during said advance thereof for operating said switches.

5. Control mechanism for an elevator car comprising, a plurality of stationary members, one for each of a plurality of floors, spaced in accordance with the distance between the floors for which they are provided, a movable member, means operable by car movement for moving said movable member with respect to said stationary members at a certain rate and in a direction with respect to said stationary members corresponding to the direction of movement of the car, a second movable member, means operable by car movement for moving said second movable member in the same direction as the first named movable member but at a rate during the starting of the car which is a multiple of said certain rate until it has advanced a certain amount with respect to said first named movable member and for thereafter moving it in unison therewith, a plurality of switches for controlling acceleration of the car, and means operable by said second movable member during said advance thereof for operating said switches in a predetermined sequence.

6. Control mechanism for an elevator car comprising, a plurality of stationary members, one for each of a plurality of floors, spaced in a certain proportion to the distance between the floors for which they are provided, a movable member, means operable incident to the starting of the car for moving said movable member with respect to said stationary members in a direction with respect to said stationary members corresponding to the direction of movement of the car to an advanced position and for thereafter moving said movable member at a rate with respect to said stationary members in accordance with movement of the car in the hatchway, a second movable member, means operable by car movement for moving said second movable member in the same direction as the first named movable member but at a rate with respect to said stationary members which during the starting of the car is a multiple of, said first named rate until it has advanced a certain amount and for thereafter moving it in unison with said first named movable member, a plurality of switches for controlling acceleration of the car, and means operable by said second movable member during said advance thereof for operating said switches in a predetermined sequence.

7. Control mechanism for an elevator car comprising, a plurality of switches, means actuated by car movement as the car leaves a floor at which it was stopped for operating said switches in sequence as the car reaches points predetermined distances from such floor, and means operable by car movement for effecting reverse operation of said switches in reverse sequence as the car reaches points predetermined distances from the floor at which a stop is to be made.

8. Control mechanism for an elevator car comprising, switching mechanism for controlling acceleration and retardation of the car, said switching mechanism being in neutral position while the car is stopped at a floor, means actuated by car movement for causing operation of said switching mechanism out of neutral position to control said acceleration during starting of the car from a floor until the car reaches a point a certain distance from such floor, and means actuated by car movement from the time the car reaches a point a certain distance from the floor at which a stop is to be made until it arrives at such floor for causing operation of said switching mechanism back to said neutral position to control retardation of the car.

9. Control mechanism for an elevator car comprising, a movable member, means actuated in accordance with car movement for moving said movable member during starting of the car from a floor at a rate which is a certain proportion to the rate of car movement until the car reaches a point a certain distance from said floor and for thereafter continuing movement of said movable member but at a rate with respect to car movement which is a fraction of said certain proportion, and means for stopping said movable member upon the arrival of the car a certain distance from the floor at which a stop is to be made and for maintaining it so until the car is brought to a stop at such floor.

10. Control mechanism for an elevator car comprising, a plurality of stationary members, one for each of a plurality of floors served by the car, spaced in accordance with the distance between the floors for which they are provided, a stationary contact on each stationary member, a member adapted for movement with respect to said stationary members, a contact carried by said movable member positioned to engage said stationary contacts when the car is stopped at the respective floors for which such contacts are provided, means actuated by car movement for moving said movable member during starting of the car at a multiple of a rate which bears the same relation to the rate of car movement as the distance between stationary members bears to the distance between the floors for which such members are provided until it has advanced a certain amount and thereafter at said rate, and means for stopping said movable member either during said advance or movement subsequent thereto upon the contact carried thereby engaging said stationary contact for a floor at which a stop is to be made and for maintaining it in such position until the car is brought to a stop at such floor.

11. Control mechanism for an elevator car comprising, a movable member, means actuated in accordance with car movement for moving said movable member during starting of the car in a certain ratio with respect to car movement until it has advanced a certain amount and for thereafter continuing movement of said movable member in accordance with car movement but in a ratio with respect to car movement which is a fraction of said certain ratio, means for stopping said movable member upon the arrival of the car at a certain distance from the floor at which a stop is to be made and for maintaining it so until the car is brought to a stop at such floor, thereby bringing said movable member into correspondence with the position of the car, and switching mechanism actuated by said movable member during its said advance with respect to the car for controlling acceleration of the car and by the continued movement of the car after the stopping of said movable member for controlling retardation of the car.

12. Control mechanism for an elevator car comprising, a movable member, means actuated in accordance with car movement for moving said movable member during starting of the car in a certain ratio with respect to car movement to advance said movable member a certain amount and thereafter continuing movement of said movable member in accordance with car move-- ment but in a ratio with respect to car movement which is half of certain ratio, and means for stop said movable member during a full speed run upon arrival of the car at a certain distance from the floor at which a stop is to be made and during a short floor run during said advance of said movable member upon the car reaching a point h if the distance of the run and for maintl ing said movable member in such position. while car is brought to a stop at such floor, thereby banging said movable member into correspondence with the position of the car.

13. Control mechanism for an elevator car com prising, switching mechanism for controlling accoloration and retardation of the car, said switch.- ing mechanism being in neutral position while the car is stopped at a floor, a plurality of stationary members, one for each of a plurality of floors served by the car, spaced in accordance with the distance between the floors for which they are provided, a member adapted for movement with respect to said stationary members and having a certain relationship thereto when the car is stopped at the respective floors, means actuated by car movement for moving said movable member during starting of the car at a multiple of a rate which bears the same relation to the rate of car movement as the distance between stationary members bears to the distance between floors for which such members are provided until it has advanced a certain amount and thereafter at said rate, means for stopping said movable member either during said advance or movement subsequent thereto upon its reaching said certain relationship with respect to said stationary member for a iloor at which a stop is to be made and for maintaining it in such position until the car is brought to a stop at such floor, means actuated by said movable member during said advance thereof for causing operation of said switching mechanism out of neutral position to control said acceleration of the car, and means actuated by car movement from the time said movable member is brought to a stop until the car arrives at the floor at which it is to be stopped for causing operation of said switching mechanism back to said neutral position to control retardation of the car.

14. Control mechanism for an elevator car comprising, a plurality of stationary members, one for each of a plurality of floors served by the car, spaced in accordance with the distance between the floors for which they are provided, a movable member having a definit position with respect to said stationary members when the car is stopped at the respective floors for which such stationary members are provided, means actuated in accordance with car movement for moving said movable member during starting of the car at a multiple of a rate which bears the same relation to the rate of car movement as the distance between stationary members bears to the distance between floors for which such members are provided until it has advanced a certain amount and for thereafter moving said movable member at said rate, means for stopping said movable member upon its arrival at said definite position with respect to said stationary member for a floor at which a stop is to be made, the continued movement of the car until it is brought to a stop at such floor taking up the advance of said movable member, and switching mechanism actuated by said movable member during its said advance for controlling acceleration of the car and by said car during said continued movement thereof after the stopping of said movable memher for controlling retardation of the car.

15. Control mechanism for an elevator car comprising, a plurality of stationary members, one for each of a plurality of floors, spaced in accordance with the distance between the floors for which they are provided, a member movable with respect to said stationary members, means for initially moving said movable member to an advanced position with respect to th car and for thereafter maintaining it in such position, means adapted upon arrival of said movable member in a certain position with respect to the stationary member for a floor at which a stop is to be made to bring said movable member to a stop, a plurality of switches, means actuated at a rate in a certain proportion to the rate of car movement during starting of the car for operating said switches in sequence as the car reaches points predetermined distances from th floor from which it is started, and means rendered effective upon the stopping of the first movable member and operable by movement of the car for effecting reverse operation of said switches in reverse sequence as the car reaches points predetermined distances from the floor at which a stop is to be made.

16. Control mechanism for an elevator car comprising, a plurality of stationary members, one for each of a plurality of floors, spaced in accordance with the distance between the floors for which they are provided, a member movable with respect to said stationary members, means for initially moving said movable member to an advanced position with respect to the car and for thereafter maintaining it in such position, circuit controlling means operable by relative movement of said movable member with respect to said stationary members upon arrival of said movable member at a certain position with respect to the stationary member and adapted upon arrival in such position with respect to the stationary mem her for a floor at which a stop is to be made, either during said advance or during said movement in advanced position, to bring said movable member to a stop, a second movable member, means for moving said second movable member in accordance with car movement initially at a rate in a certain ratio with respect to the rate of car movement until it has advanced a certain amount with respect to the car and thereafter at half said initial rate, means operable after the stopping of the first movable member to bring said second movable member to a stop, a plurality of switches, means operable by said second movable member during said initial movement thereof for operating said switches in a certain sequence, and means operabl by said car alter said second movable member has been brought to a stop for effecting reverse operation of said switches in reverse sequence.

17. Control mechanism for an elevator car comprising, a plurality of stationary members. one for each of a plurality of floors, spaced in a certain proportion to the distance between the floors for which they are provided, a stationary contact on each of said stationary members, a member movable with respect to said stationary members, a contact carried by said movable member for engaging said stationary contacts, a 

